Concrete mixer



P 1933- G. JAEGER El AL 1,928,380

CONCRETE MIXER Filed April 9, 1931 -5 I H i 45 I ZSnvenfor GEBHARD JAEG ER 1 7.

JOSEPH EGGERT mttomeg .5

Patented Sept. 26, 1933 NT OFFICE CONCRETE MIXER Gebhard Jaeger and Joseph Eggert, Columbus, Ohio; Emma L. Keny administratrix of said Joseph Eggert, deceased, assignors to The Jaeger Machine Company, Columbus, Ohio,

a corporation of Ohio Application April 9, 1931. Serial No. 528,806

2 Claims.

The invention relates more especially to what are called truck concrete mixers intended more particularly for mixing the concrete while transporting it to or for delivering ready-mixed con- -crete at the place of use, the principal object of the invention being to provide an improved and simplified construction whereby the concrete may be thoroughly and properly mixed in a horizontally arranged rotated drum and from which it may be discharged by rotation of the drum. Other objects of the invention will appear from the disclosure herein.

The invention is embodied in the example herein shown and described, the features of novelty being pointed out in the claims.

In order that the said invention may be clearly understood and readily carried into effect, the same will now be described more fully, by way of said example, with reference to the accompanying drawing, in which- Figure l is a side view of a truck concrete mixer according to the invention with parts broken out.

Fig. 2 is a view of the rear end of the mixing drum, on a larger scale.

Fig. 3 is a central longitudinal sectional view of the mixing drum with parts in full.

Fig. 4'. is'a cross sectional detail, on a larger scale, of the closure for the charging opening oi the mixing drum.

'Figs. 5, 6 and '7 are plan, end, and side views of an air or gas venting means for the drum.

The mixing and transporting drum is mounted on an ordinary motor driven chassis having an engine within the usual hood 8, a driver's cab 9, a truck bed 10 supported by wheels 11, the rear pair of which is driven through a change speed gearing, not shown, but as usual.

) The mixing and transporting vessel is mounted to turn on a horizontal axis on a forward standard 12 and rear roller bearings 13, 13, said vessel having an intermediate cylindrical portion 17 extended forwardly and rearwardly as tapered portions 17' and 17 The rear tapered portion of the vessel 17'' is provided with an annular flanged track 14 resting and traveling on roller bearings 13, 13, and swivelly secured to a cross bar 15 of the chassis, between said bearings is a flanged roiler 16, the flange of which projects above the flange of the track to prevent the vessel from bouncing upward at its rear end on the chassis. The forward head of the drum is permanently closed except for the water pipe, while its rear end has an opening for the discharge 01' the mixed concrete. Within the vessel and rotating with it are two oppositely disposed spiral mixing blades 19, 19, each terminating at therear in spiral portions 19 19 in the tapered portion 1'7 and terminating at their forward ends in the forward portion 1? of the drum as spiral portions 19 19*. Extended axial- 1y through the forward head of the mixing vessel is a stationary pipe 20 for conducting Water from a tank 50 to the interior of the drum. Rotating on said pipe 20 is a sleeve 21 carrying a screw-blade 21", the pitch of which is opposed to that of the spiral mixing blades. The pipe 20 is provided with'discharge openings (not shown) and to protect said openings against the action of concrete materials they are surrounded by a cone-shaped shield 20 of metal or other stout material secured to the shaft. Said shield is pro vided with a suitable valve (not shown) adapted to prevent the ingress of materials and permit discharge only of water.

The pipe 20, which is closed at its rear end,

has coupled to it for support by a coupling 22 a rear tubular extension 22 having an internally threaded bushing to receive a screw 23 adapted to be turned by a hand wheel 24. The character 25 designates a cover for the discharge opening of the mixing drum, said cover having a hub provided with a central tube fixed thereto that fits around and slides on the tube 22 to keep the screw 23 inclosed when drawn out. The hub of the hand wheel is provided with an annular projection 24 to engage lugs 24 on the hub of the cover so that the cover can be opened or closed by turning the hand wheel. 'It will be observed that the water supply pipe extension thus affords a support for the cover and its operating means.

The side of the mixing drum is provided with a beveled depressed ring 26 forming a charging opening for the drum, said opening being provided with a removable cover 27 sustained by a keeper bar 28 pivoted at'one end on a swiveled pivoted pin 29 at one side of the opening, and having a hook 30 at its other end to engage a headed pin 21 at the opposite side of the opening. Said cover 27 is centrally swiveled on a hand operated screw 32 engaging the keeper bar so that pressure can be applied to the cover by turning the screw to make it fit tightly on the seat afforded by the beveled ring of the drum.

Near its forward end on the tapered portion the mixing drum is provided with a peripheral gear rack 33. Mounted longitudinally in. a suitable bearing on the truck bed is a shaft 34 having at its rear end a pinion 35 engaging said a sprocket chain 36, the latter connected with a sprocket wheel fixed on the tubular shaft carrying the spiral screw so that the mixing drum with its mixing blades and said tubular shaft with its blade shall be driven in opposite directions.

The power for driving the shaft 34 may be derived from the vehicle propelling engine but, in the instance shown, there is secured to the truck bed an engine 3'7 distinct from that of the vehicle propelling engine, said engine 3'7 being preferably of the usual petrol type for said purpose. Means are provided for applying, stopping and reversing the direction of motion of the drum and shaft 34 comprising a suitable power translating mechanism (not shown in detail) within a housing 34.

To release air or gas pressure created in the mixing drum the forward end thereof is shown as provided with a vent that is normally held closed by an external valve (see Fig. 7) by a spring 41 between the valve and a bracket 42. Said bracket is provided with two cam flanges 43 and 44 spaced apart. The stem of the valve 40 has fixed to it an arm 45 adapted, when the mixing drum is rotated, to strike the end of an arm 46 fixed on a standard and carry the same onto the cam and thereby lift the valve to open the vent. When the said arm 45, in the rotation of the drum, passes the end of the arm 46 the pressure of the spring 41 tends to draw said arm off the cam and close the valve on said vent. One of the cams 43 and 44.serves to open the vent when the drum is turned in one direction and the other cam serves to open the vent when the drum is rotated in the opposite direction.

It will be observed that each rotation of the drum causes an actuation of the arm 45 whether the drumrotates in one direction or the other. According to the present invention it is designed generally that the normal mixing operation shall be performed by rotation of the mixing drum in one direction and the discharge effected by rotation of the reverse direction, when the discharge cover is removed. Such discharge is effected by the extension of the mixing blades into the tapered rear portion of the drum.

When the discharge cover is closed the tapered forward and rear ends of the drum tend to concentrate by gravity thematerial in the central cylindrical part of the drum because of themclination of the bottoms of said tapered portions toward said central cylindrical portion. In the mixing operation the central screw cooperates with the main mixing blades, the latter cascading the concrete materials onto the said central screw and tending to counteract some of the longitudinal movement caused by the main mixing blades. When the drum is to be discharged motion of the drum is reversed from that employed in mixing and the cover is drawn out by turning the hand wheel 24 in the proper direction. The tapered discharge end of the drum is provided with a rearwardly and outwardly flared collar 47 adjacent and around the lower side of which is fixedly supported a slanting spout 48 adapted to direct the mixed concrete when being discharged into a suitable receptacle, a wheelbarrow for example.

The forms of the parts can be changed without departing from the gist of the invention as claimed. i

What we claim is:

1. A truck concrete mixer and agitator including in combination, a truck bed, a pair of vessel supporting rollers journaled opposite each other on the truck bed, a rotatable mixing vessel having fixed on its exterior an.annular track having a flange offset from the vessel and extending substantially parallel to the axis of rotation of said vessel, said track traveling at its outer face on said rollers, and means attached to the truck bed and extending over the inner face of said fiange and between said face and the mixing vessel to prevent bouncing of the vessel with respect to said truck bed.

2. A truck concrete mixer and agitator including in combination, a truck bed, a pair of vessel supporting rollers journaled opposite each other on the truck bed, a rotatable mixing vessel having fixed on its exterior an annular track having a flange offset from the vessel and extending substantially parallel to the axis of rotation of said vessel, said track traveling at its outer face on said rollers, and means consisting of a swiveled roller secured to and mounted on the truck bed, said roller having a projecting rim extending over the inner face of the fiange of said track and be tween said face and the mixing 'vessel to prevent bouncing of the vessel with respect to said track.

GEBHARD JAEGER. JOSEPH EGGERT. 

